Polymeric amine synergist compositions

ABSTRACT

The present disclosure is drawn to polymeric amine synergist compositions. The polymeric amine synergist composition can include a polymeric amine synergist including an aminobenzene modified with a polyether chain connecting to the aminobenzene through an ether linkage. The polymeric amine synergist can be present in a reaction product mixture with either i) an aminophenol, or ii) a carbonate base.

BACKGROUND

The inkjet printing industry uses various types of inks, such asoil-based inks, solvent-based (non-aqueous) inks, water-based inks, andsolid inks (which are melted in preparation for dispensing).Solvent-based inks are fast drying, and as a result, are widely used forindustrial printing. When solvent-based inks containing binders andother ingredients are jetted onto a substrate, the solvent(s) partiallyor fully evaporate from the ink, leaving the binder and otheringredients such as pigment particles on the printed substrate in theform of a dry film. During the drying process, the solvents, which areoften volatile organic compounds (VOC), emit vapors, and therefore canpollute the environment. The amount of pollution produced can increasegreatly with higher printing speeds or for wide format images, wherelarge amounts of ink are deposited onto a substrate.

As a result of this and other concerns, efforts related to preparinginks that are environmentally friendly have moved some research in thedirection of water-based inks. However, radiation-curable (orphoton-curable) water-based ink compositions are noticeably limitedamong available options due to their specific formulation properties.Accordingly, the development of radiation radiation-curable water-basedink compositions that exhibit, when printed, specific desirable printingproperties, e.g., jetting properties as well as improved adhesion, wouldbe an advancement in the field of inkjet technology.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram depicting a method of making a polymeric aminesynergist in accordance with an example of the present disclosure; and

FIG. 2 is a diagram depicting a method of making a photo curable ink inaccordance with examples of the present disclosure.

DETAILED DESCRIPTION

The present disclosure is drawn to polymeric amine synergistcompositions and methods of preparing polymeric amine synergists. In oneexample, the polymeric amine synergist compositions can include apolymeric amine synergist including an aminobenzene modified with apolyether chain connecting to the aminobenzene through an ether linkage.The polymeric amine synergist can be present in a reaction productmixture with either i) an aminophenol, or ii) a carbonate base. Forexample, the aminophenol and/or the carbonate base can remain in thecomposition in minor or even residual amounts after carrying out certainmethods of the present disclosure.

The present disclosure also provides methods of making polymeric aminesynergists including an aminobenzene modified with a polyether chainconnecting to the aminobenzene through an ether linkage. The polymericamine synergists can be water soluble and stable in aqueous inks, suchas aqueous thermal inkjet inks, for example. The polymeric aminesynergists also resist migration in the ink after curing. Thus, thepolymeric amine synergists of the present disclosure overcome some ofthe drawbacks of other synergists and photo initiators which do notbehave in this positive manner in aqueous systems. Some small molecularweight synergists, such as methyldiethanolamine, triethanolamine, andits analogs, can have unwanted odor, toxicity, and migration in curedmaterials. On the other hand, many polymeric synergists and photoinitiators are not water soluble and are difficult to formulate intoaqueous inks. Thus, in accordance with this, the present disclosure isdrawn to improved methods of making polymeric amine synergists. Themethods described herein include reaction pathways that are simple andprovide high yields of the polymeric amine synergists. These methods canbe adapted for large-scale synthesis of polymeric amine synergists.

Thus, in one example, and as shown in FIG. 1, a method of making apolymeric amine synergist 100 can include the step of reacting 110 anaminophenol, a polyether modified with a leaving group, and a carbonatebase in a single reaction step to yield a polymeric amine synergist thatis an aminobenzene modified with a polyether chain connecting to theaminobenzene through an ether linkage.

In another example, and as shown in FIG. 2, a method of making a photocurable ink 200 can include preparing 210 a polymeric amine synergist,and admixing 220 the polymeric amine synergist; a photo reactive binder;a photo initiator; a colorant; and a liquid vehicle including co-solventand water together to form the ink. Specifically, the step of preparingthe polymeric amine synergist can include reacting an aminophenol, apolyether modified with a leaving group, and a carbonate base in asingle reaction step to yield a polymeric amine synergist that is anaminobenzene modified with a polyether chain connecting to theaminobenzene through an ether linkage.

In another example, a photo curable ink can include a polymeric aminesynergist composition having a polymeric amine synergist including anaminobenzene modified with a polyether chain connecting to theaminobenzene through an ether linkage. The ink can further include anaminophenol, or a carbonate base, or combination thereof, e.g., as aresidual component(s) remaining after carrying out a method of thepresent disclose. The ink can further include a photo reactive binder; aphoto initiator; a colorant; and a liquid vehicle including co-solventand water.

Accordingly, a polymeric amine synergist can include an aminobenzenemodified with a polyether chain connecting to the aminobenzene throughan amide linkage. As used herein, “aminobenzene” refers to the compoundalso referred to as aniline or phenylamine, as well as analogs of thiscompound with attached R-groups, such as dimethylaniline. The aminogroup of the aminobenzene can be a primary amine, secondary amine, ortertiary amine.

The polyether chain can be a polyglycol, paraformaldehyde, or otherpolyether. For example, the polyether chain can be polyethylene glycol(PEG), methoxypolyethylene glycol (MPEG), polypropylene glycol (PPG),polybutylene glycol (PBG), or a polyglycol copolymer. In one specificexample, the polyether chain can be selected from polyethylene glycol,polypropylene glycol, and a copolymer of polyethylene glycol andpolypropylene glycol. In another specific example, the polyether chaincan be derived from a portion of a commercially available polyetheramine such as Jeffamine® ED-900, Jeffamine® M-1000 (both available fromHuntsman Corporation), or others. Various molecular weights of polyethercan be suitable. The type of polyether chain and the molecular weight ofthe polyether chain can in some cases affect the solubility of the finalpolymeric amine synergist. For example, a higher ratio of oxygen atomsto carbon atoms in the polyether chain tends to make the polymeric aminesynergist more soluble. The molecular weight of the polyether chain canalso affect the degree to which the polymeric amine synergist canmigrate in a cured ink. Longer polyether chains can make it moredifficult for the polymeric amine synergist to move within a cured ink,thus decreasing migration. Therefore, the type of polyether chain can beselected to give good water solubility and low migration of thepolymeric amine synergist in cured ink. In one example, the polyetherchain can be a polyglycol having at least 5 glycol monomer units.

The polyether chain can connect to the aminobenzene through an etherlinkage. As used herein, connecting to the aminobenzene through an etherlinkage means that a single oxygen atom is bonded both to a carbon atomin the aromatic ring of the aminobenzene and to a carbon atom in thepolyether chain. This ether linkage can be formed by a suitablereaction, such as a substitution reaction or a condensation reaction.

The aminobenzene, polyether chain, and ether linkage do not necessarilymake up the entire polymeric amine synergist. For example, additionalgroups can be attached along the polyether chain or at the opposite endof the polyether chain. In some cases, one or more additionalaminobenzene moieties can be attached to the polyether chain. Theseadditional aminobenzene moieties can connect to the polyether chainthrough ether linkages. In one example, an additional aminobenzenemoiety can connect to an opposite end of the polyether chain through anether linkage. In other examples, the polyether chain can have multiplebranches and each branch can terminate with an aminobenzene moietyconnected to the polyether chain through an ether linkage. Specificexamples of such polymeric amine synergists are described in detailbelow.

In some examples, the aminobenzene with the ether linkage can have ageneral formula according to Formula 1:

In Formula 1, the ether linkage is illustrated as an oxygen atom bondedto the aromatic ring of the aminobenzene. The ether linkage can bebonded to any of the available carbon atoms in the ring by replacing ahydrogen atom. The groups R₁ and R₂ can be independently a hydrogenatom, an unsubstituted alkyl, a substituted alkyl, an unsubstitutedalkenyl, a substituted alkenyl, an unsubstituted aryl, a substitutedaryl, an unsubstituted aralkyl, a substituted aralkyl, a halogen atom,—NO₂, —O—R_(d), —CO—R_(d), —CO—O—R_(d), —O—CO—R_(d), —CO—NR_(d)R_(e),—NR_(d)R_(e), —NR_(d)—CO—R_(e), —NR_(d)—CO—O—R_(e),—NR_(d)—CO—NR_(e)R_(f), —SR_(d), —SO—R_(d), —SO₂—R_(d), —SO₂—O—R_(d),—SO₂NR_(d)R_(e), or a perfluoroalkyl group, wherein R_(d), R_(e), andR_(f) are independently a hydrogen atom, an unsubstituted alkyl, asubstituted alkyl, an unsubstituted alkenyl, a substituted alkenyl, anunsubstituted aryl, a substituted aryl, an unsubstituted aralkyl, or asubstituted aralkyl. In one specific example, R₁ and R₂ can each be ahydrogen atom. Formula 1 illustrates only the aminobenzene with theether linkage. A complete polymeric amine synergist can be formed bycombining an aminobenzene and ether linkage as in Formula 1 with apolyether chain. The polyether chain can be bonded to the oxygen atom ofthe ether linkage

In some examples, the polymeric amine synergist can have a generalformula according to one of Formulas 2-5:

In each of Formulas 2-5, the groups R₁, R₂, and R₃ can independently bea hydrogen atom, an unsubstituted alkyl, a substituted alkyl, anunsubstituted alkenyl, a substituted alkenyl, an unsubstituted aryl, asubstituted aryl, an unsubstituted aralkyl, a substituted aralkyl, ahalogen atom, —NO₂, —O—R_(d), —CO—R_(d), —CO—O—R_(d), —O—CO—R_(d),—CO—NR_(d)R_(e), —NR_(d)R_(e), —NR_(d)—CO—R_(e), —NR_(d)—CO—O—R_(e),—NR_(d)—CO—NR_(e)R_(f), —SR_(d), —SO—R_(d), —SO₂—R_(d), —SO₂—O—R_(d),—SO₂NR_(d)R_(e), or a perfluoroalkyl group. In these examples, R_(d),R_(e), and R_(f) can independently be a hydrogen atom, an unsubstitutedalkyl, a substituted alkyl, an unsubstituted alkenyl, a substitutedalkenyl, an unsubstituted aryl, a substituted aryl, an unsubstitutedaralkyl, or a substituted aralkyl. In one specific example, R₁ to R₃ caneach be a hydrogen atom. The number of monomer units n can be anyinteger from 5 to 200.

As shown in Formulas 2-5, the polymeric amine synergist can include 1,2, 3, or 4 aminobenzene moieties connected to a branching polyetherchain. In other examples, the polyether chain can have more than 4branches terminating in aminobenzene moieties.

In one example, the polymeric amine synergist can have a general formulaaccording to Formula 6:

In the specific example described by Formula 6, n can be any integer,e.g., 5 to 200.

The molecular weight of the polymeric amine synergist can affect itsdegree of migration in cured ink. For clarity, unless otherwise noted,molecular weights for polymers are weight average molecular weights(Mw). In accordance with this, a polymeric amine synergist with a weightaverage molecular weight (Mw) of about 500 Mw or more can have reducedmigration in cured ink compared with a small molecule photo initiator orsensitizer. Migration can be further reduced by increasing the molecularweight of the polymeric amine synergist to about 1000 Mw or more. In oneexample, the polymeric amine synergist can have a molecular weight fromabout 500 Mw to about 5000 Mw. Polyethers of various molecular weightsare available, allowing for the production of polymeric amine synergistswith various weight average molecular weights. In some examples, thepolyether chain can be selected from PEG 550, PEG 600, and PEG 1000. Inpolymeric amine synergists having multiple aminobenzene moieties, asmaller molecular weight polyether chain can be used while stillmaintaining a high overall molecular weight of the polymeric aminesynergists. The molecular weight of the polymeric amine synergist canalso be changed by adding R groups to the aminobenzene. It is noted thatwhen referring to “R groups” generically herein, this term is defined toinclude at least H and organic side chain side groups and other specificconstituents described and defined elsewhere herein, e.g., R, R₁, R₂,R₃, R_(d), R_(e), R_(f), etc.

The molecular weight (Mw) of the polymeric amine synergist can alsoaffect its solubility in water. In some cases, the polyether chain canbe a water soluble polyether. Although the aminobenzene alone can beinsoluble in water, adding the soluble polyether chain can make theentire polymeric amine synergist soluble. In such cases, the solublepolyether can have a sufficient molecular weight so that its solubilityproperties overcome the insolubility of the aminobenzene. In othercases, water soluble R groups can be added to the aminobenzene toincrease the solubility of the polymeric amine synergist. In oneexample, the polymeric amine synergist can have a water solubility of atleast 0.5 wt %.

Typical aqueous ink jet inks can have a pH in the range of 7 to 12. Somecommercially available photo initiators and synergists with esterlinkages can break down in such basic conditions. The ether linkage inthe polymeric amine synergists according to the present disclosure canbe stable under these conditions. In some examples, the polymeric aminesynergist can be stable in water up to a pH from 7 to 12. In otherexamples, the polymeric amine synergist can be stable in water up to apH of 8 or higher. As used herein, “stable” refers to the ability of thepolymeric amine synergist to have a shelf life of at least 1 year.Typically, aqueous ink jet inks can have a shelf life of greater than 1year, greater than 2 years, or longer.

The polymeric amine synergist described above can be formed using amulti-step process involving a reaction with sodium hydroxide. Areaction pathway for one example of this process is shown in Formula 7:

In the pathway shown in Formula 7, R₁ to R₃ each independently representa hydrogen atom, a substituted or unsubstituted alkyl, alkenyl, aryl oraralkyl group or a group selected from a halogen atom, —NO₂, —O—R_(d),—CO—O—R_(d), —O—CO—R_(d), —CO—NR_(d)R_(e), —NR_(d)R_(e),—NR_(d)—CO—R_(e), —NR_(d)—CO—O—R_(e), —NR_(d)—CO—NR_(e)R_(f), —SR_(d),—SO—R_(d), —SO₂—R_(d), —SO₂—O—R_(d), —SO₂NR_(d)R_(e) or a perfluoroalkylgroup. R_(d), R_(e) and R_(f) independently represent a hydrogen or asubstituted or unsubstituted alkyl, alkenyl, aryl or aralkyl group. Thenumber of monomer units n can be any integer from 5 to 200. The group Ycan be a leaving group such as —Cl, —Br, —I, —OTs, or —OTf.

As shown in Formula 7, a monosubstituted polyethylene glycol ether (1)is reacted with a leaving group to form a leaving group modifiedpolyethylene glycol (2). Various reagents can be used to add the leavinggroup. For example, a halogenation reagent can be used to add —Cl, —Br,or —I leaving groups; a tosylation reagent can be used to add a —OTsleaving group; and a triflating reagent can be used to add a —OTfleaving group. An aminophenol (3) is reacted with NaOH to form acorresponding sodium salt (4). The sodium salt is then reacted with theleaving group modified polyethylene glycol (2) to form the polymericamine synergist. Lines leading to the center of aromatic rings in theaminophenol (3), the sodium salt (4), and the final polymeric aminesynergist signify that the group can be attached at any availablelocation on the ring.

The reaction pathway shown in Formula 7 is complex and can result in lowyields, due to the steps of reacting the aminobenzene with NaOH to formthe sodium salt, followed by reacting the sodium salt with the leavinggroup modified polyethylene glycol. This pathway typically results inyields ranging from 10% to 50%. The leaving group modified polyethyleneglycol cannot be reacted with the aminobenzene and the NaOHsimultaneously, because the hydroxyl (OH⁻) produced from the NaOH wouldreplace the leaving group on the leaving group modified polyethyleneglycol. The polyethylene glycol would then not be able to connect to theaminobenzene. For this reason, NaOH is reacted with the aminobenzenefirst to form a sodium salt of the aminobenzene, and then in a separatestep the sodium salt is reacted with the leaving group modifiedpolyethylene glycol to form the final polymeric amine synergist.

To reduce the complexity of the synthesis process and increase the yieldof polymeric amine synergist, a different reaction pathway can involvereacting the aminobenzene directly with the leaving group modifiedpolyethylene glycol in a single step. An example of such a pathway isshown in Formula 8:

In the pathway shown in Formula 8, R₁ to R₃ each independently representa hydrogen atom, a substituted or unsubstituted alkyl, alkenyl, aryl oraralkyl group or a group selected from a halogen atom, —NO₂, —O—R_(d),—CO—R_(d), —CO—O—R_(d), —O—CO—R_(d), —CO—NR_(d)R_(e), —NR_(d)R_(e),—NR_(d)—CO—R_(e), —NR_(d)—CO—O—R_(e), —NR_(d)—CO—NR_(e)R_(f), —SR_(d),—SO—R_(d), —SO₂—R_(d), —SO₂—O—R_(d), —SO₂NR_(d)R_(e) or a perfluoroalkylgroup. R_(d), R_(e) and R_(f) independently represent a hydrogen or asubstituted or unsubstituted alkyl, alkenyl, aryl or aralkyl group. Thenumber of monomer units n can be any integer from 5 to 200. The group Ycan be a leaving group such as —Cl, —Br, —I, —OTs, or —OTf.

According to this pathway, a monosubstituted polyethylene glycol ether(1) is reacted with a leaving group to form a leaving group modifiedpolyethylene glycol (2). Then, an aminophenol (3) is reacted directlywith the leaving group modified polyethylene glycol (2) in the presenceof a base and dimethylformamide (DMF) at reflux conditions. The baseused in this reaction is a base other than NaOH, which does not replacethe leaving group of the leaving group modified polyethylene glycol (2).Without being bound to a particular mechanism, it is believed that thebase can be a base that does not produce a hydroxyl group that wouldreplace the leaving group on the leaving group modified polyethyleneglycol (2). In certain examples, the base can be a carbonate base, suchas sodium carbonate (Na₂CO₃), potassium carbonate (K₂CO₃) or cesiumcarbonate (Cs₂CO₃). In this reaction, the aminophenol (3) becomes bondeddirectly to the polyethylene glycol through an ether linkage.

Thus, the step of reacting the aminophenol with NaOH to form a sodiumsalt can be eliminated, simplifying the process for synthesizing thepolymeric amine synergist. This pathway can also provide a higher yield.In some examples, the yield of the polymeric amine synergist can be from75% to 95%.

In more general terms, a method of making a polymeric amine synergist inaccordance with the present disclosure can include: reacting anaminophenol, a polyether modified with a leaving group, and a carbonatebase in a single reaction step to yield a polymeric amine synergist thatis an aminobenzene modified with a polyether chain connecting to theaminobenzene through an ether linkage. The polymeric amine synergist canhave any of the structures described above.

In some examples, the aminophenol can have a general formula accordingto Formula 9:

In Formula 9, the —OH group can be bonded to any of the available carbonatoms in the aromatic ring by replacing a hydrogen atom. The groups R₁and R₂ can be independently selected from: a hydrogen atom, anunsubstituted alkyl, a substituted alkyl, an unsubstituted alkenyl, asubstituted alkenyl, an unsubstituted aryl, a substituted aryl, anunsubstituted aralkyl, a substituted aralkyl, a halogen atom, —NO₂,—O—R_(d), —CO—R_(d), —CO—O—R_(d), —O—CO—R_(d), —CO—NR_(d)R_(e),—NR_(d)R_(e), —NR_(d)—CO—R_(e), —NR_(d)—CO—O—R_(e),—NR_(d)—CO—NR_(e)R_(f), —SR_(d), —SO—R_(d), —SO₂—R_(d), —SO₂—O—R_(d),—SO₂NR_(d)R_(e), and a perfluoroalkyl group, wherein R_(d), R_(e), andR_(f) are independently selected from: a hydrogen atom, an unsubstitutedalkyl, a substituted alkyl, an unsubstituted alkenyl, a substitutedalkenyl, an unsubstituted aryl, a substituted aryl, an unsubstitutedaralkyl, and a substituted aralkyl. In one specific example, R₁ and R₂can each be a hydrogen atom. In other examples, the aminophenol can bean alkyl aminophenol or a dialkylaminophenol.

In some examples, the carbonate base used in the method can be sodiumcarbonate, potassium carbonate, cesium carbonate, sodium bicarbonate,potassium bicarbonate, cesium bicarbonate, or a combination thereof. Inone specific example, the carbonate base can include sodium carbonate ora mixture of sodium carbonate and another base.

The carbonate base can generally be added to the reaction in an amountthat is effective for bonding the aminophenol to the leaving groupmodified polyether. In some examples, the amount of carbonate base usedcan be 1 equivalent or more of the carbonate base, relative to theamount of the aminophenol present in the reaction. In further examples,the amount of carbonate base can be from about 1 equivalent to about 2equivalents, relative to the amount of the aminophenol. In a specificexample, the amount of carbonate base can be from about 1.1 equivalentsto about 1.2 equivalents, relative to the amount of the aminophenol.

Although the reaction pathway shown in Formula 8 uses DMF as a solventin the reaction between the aminophenol and the polyether modified witha leaving group, other solvents can also be used. Suitable solvents forthis reaction can include DMF, THF, ethyl acetate, toluene, xylene, andmixtures thereof.

The polyether modified with a leaving group used in the reaction can beformed by reacting a leaving group with a polyether chain. In someexamples, the polyether chain can include polyethylene glycol,polypropylene glycol, or a copolymer of polyethylene glycol andpolypropylene glycol. In further examples, the polyether chain can bePEG 550, PEG 600, or PEG 1000.

In additional examples, the polyether modified with the leaving groupcan have a general formula according to one of Formulas 10-13:

In each of Formulas 10-13, the group R₃ can be a hydrogen atom, anunsubstituted alkyl, a substituted alkyl, an unsubstituted alkenyl, asubstituted alkenyl, an unsubstituted aryl, a substituted aryl, anunsubstituted aralkyl, a substituted aralkyl, a halogen atom, —NO₂,—O—R_(d), —CO—R_(d), —CO—O—R_(d), —CO—NR_(d)R_(e), —NR_(d)R_(e),—NR_(d)—CO—R_(e), —NR_(d)—CO—O—R_(e), —NR_(d)—CO—NR_(e)R_(f), —SR_(d),—SO—R_(d), —SO₂—R_(d), —SO₂—O—R_(d), —SO₂NR_(d)R_(e), or aperfluoroalkyl group. In these examples, R_(d), R_(e), and R_(f) canindependently be a hydrogen atom, an unsubstituted alkyl, a substitutedalkyl, an unsubstituted alkenyl, a substituted alkenyl, an unsubstitutedaryl, a substituted aryl, an unsubstituted aralkyl, or a substitutedaralkyl. In one specific example, R₃ can be a hydrogen atom. The numberof monomer units n can be any integer from 5 to 200. The group Y can bechloride, bromide, iodide, tosylate, or triflate.

Another example of a general pathway for forming a polymeric aminesynergist in accordance with the present disclosure is shown in Formula14:

In the pathway shown in Formula 14, R₁ and R₂ each independentlyrepresent a hydrogen atom, a substituted or unsubstituted alkyl,alkenyl, aryl or aralkyl group or a group selected from a halogen atom,—NO₂, —O—R_(d), —CO—R_(d), —CO—O—R_(d), —O—CO—R_(d), —CO—NR_(d)R_(e),—NR_(d)R_(e), —NR_(d)—CO—R_(e), —NR_(d)—CO—O—R_(e),—NR_(d)—CO—NR_(e)R_(f), —SR_(d), —SO—R_(d), —SO₂—R_(d), —SO₂—O—R_(d),—SO₂NR_(d)R_(e) or a perfluoroalkyl group. R_(d), R_(e) and R_(f)independently represent a hydrogen or a substituted or unsubstitutedalkyl, alkenyl, aryl or aralkyl group. The number of monomer units n canbe any integer from 5 to 200. The group Y can be a leaving group such as—Cl, —Br, —I, —OTs, or —OTf.

According to this pathway, polyethylene glycol (4) is reacted with aleaving group reagent to form a leaving group modified polyethyleneglycol (5). An aminophenol (3) is reacted with the leaving groupmodified polyethylene glycol and a carbonate base to form the polymericamine synergist. Lines leading to the center of aromatic rings in theaminophenol (3) and the final polymeric amine synergist signify that thegroup can be attached at any available location on the ring.

A further example of a general pathway for forming a polymeric aminesynergist keeping with the present disclosure is shown in Formula 15:

In the pathway shown in Formula 15, R₁ to R₃ each independentlyrepresent a hydrogen atom, a substituted or unsubstituted alkyl,alkenyl, aryl or aralkyl group or a group selected from a halogen atom,—NO₂, —O—R_(d), —CO—R_(d), —CO—O—R_(d), —O—CO—R_(d), —CO—NR_(d)R_(e),—NR_(d)R_(e), —NR_(d)—CO—R_(e), —NR_(d)—CO—O—R_(e),—NR_(d)—CO—NR_(e)R_(f), —SR_(d), —SO—R_(d), —SO₂—R_(d), —SO₂—O—R_(d),—SO₂NR_(d)R_(e) or a perfluoroalkyl group. R_(d), R_(e) and R_(f)independently represent a hydrogen or a substituted or unsubstitutedalkyl, alkenyl, aryl or aralkyl group. The number of monomer units n canbe any integer from 5 to 200. The group Y can be a leaving group such as—Cl, —Br, —I, —OTs, or —OTf.

According to this pathway, a glycerol polyethylene glycol derivative (6)is reacted with a leaving group reagent to form a leaving group modifiedglycerol polyethylene glycol derivative (7). An aminophenol (3) isreacted with the leaving group modified glycerol polyethylene glycolderivative and a carbonate base to form the polymeric amine synergist.Lines leading to the center of aromatic rings in the aminophenol (3) andthe final polymeric amine synergist signify that the group can beattached at any available location on the ring.

Yet another example of a general pathway for forming a polymeric aminesynergist in accordance with the present disclosure is shown in Formula16:

In the pathway shown in Formula 16, R₁ and R₂ each independentlyrepresent a hydrogen atom, a substituted or unsubstituted alkyl,alkenyl, aryl or aralkyl group or a group selected from a halogen atom,—NO₂, —O—R_(d), —CO—R_(d), —CO—O—R_(d), —O—CO—R_(d), —CO—NR_(d)R_(e),—NR_(d)R_(e), —NR_(d)—CO—R_(e), —NR_(d)—CO—O—R_(e),—NR_(d)—CO—NR_(e)R_(f), —SR_(d), —SO—R_(d), —SO₂—R_(d), —SO₂—O—R_(d),—SO₂NR_(d)R_(e) or a perfluoroalkyl group. R_(d), R_(e) and R_(f)independently represent a hydrogen or a substituted or unsubstitutedalkyl, alkenyl, aryl or aralkyl group. The number of monomer units n canbe any integer from 5 to 200. The group Y can be a leaving group such as—Cl, —Br, —I, —OTs, or —OTf.

According to this pathway, a pentaerythritol polyethylene glycolderivative (8) is reacted with a leaving group to form a leaving groupmodified pentaerythritol polyethylene glycol derivative (9). Anaminophenol (3) is reacted with the leaving group modifiedpentaerythritol polyethylene glycol derivative and a carbonate base toform the polymeric amine synergist. Lines leading to the center ofaromatic rings in the aminophenol (3) and the final polymeric aminesynergist signify that the group can be attached at any availablelocation on the ring.

Formula 17 illustrates a detailed synthetic pathway for one example of apolymeric amine synergist in accordance with the present disclosure:

According to this pathway, 4-aminophenol (10) is reacted with sodiumborohydride and formaldehyde in methanol to yield 4-dimethylaminophenol(11). Polyethylene glycol (12) is reacted with thionyl chloride in thepresence of DMF to give dichloro polyethylene glycol (13). Finally,reaction of the 4-dimethylaminophenol (11) with the dichloropolyethylene glycol (13) in DMF under reflux in the presence of acarbonate base gives the desired polymeric amine synergist (14) in highyield.

An alternative pathway for synthesizing the same polymeric aminesynergist is shown in Formula 18:

In this pathway, polyethylene glycol (12) is reacted withtoluenesulfonyl chloride in the presence of pyridine to givepolyethylene glycol di-tosylate (15). Then, 4-dimethylaminophenol (11)is reacted with the polyethylene glycol di-tosylate (15) in DMF underreflux in the presence of a carbonate base to give the desired polymericamine synergist (14) in high yield.

A detailed synthetic pathway for forming another example of a polymericamine synergist in accordance with the present disclosure is shown inFormula 19:

In this pathway, mono-methyl polyethylene glycol ether (16) is reactedwith thionyl chloride in the presence of DMF to give chloro mono-methylpolyethylene glycol ether (17). Then, 4-dimethylaminophenol (11) isreacted with the chloro mono-methyl polyethylene glycol ether (17) inDMF under reflux in the presence of a carbonate base to give the desiredpolymeric amine synergist (18) in high yield.

Formula 20 illustrates an alternate pathway for forming the samepolymeric amine synergist:

According to this pathway, mono-methyl polyethylene glycol ether (16) isreacted with p-toluenesulfonyl chloride in the presence of pyridine togive mono-methyl polyethylene glycol tosylate (19). Then,4-dimethylaminophenol (11) is reacted with the mono-methyl polyethyleneglycol tosylate (19) in DMF under reflux in the presence of a carbonatebase to give the desired polymeric amine synergist (18) in high yield.

As mentioned, the present disclosure also extends to reaction productmixtures made using the reaction pathways described above. Generally, areaction product mixture prepared by performing the reaction describedabove can include a polymeric amine synergist set forth herein. Thereaction product mixture can also include excess reactants, such as anaminophenol, a polyether modified with a leaving group, a carbonatebase, or a combination thereof. In some examples, the reaction productmixture can include a polymeric amine synergist that is an aminobenzenemodified with a polyether chain connected to the aminobenzene through anether linkage, and either an aminophenol, or a carbonate base. Inexamples including the aminophenol, the aminophenol can be the samecompound used as a reactant to form the polymeric amine synergist.

In further examples, the reaction product mixture can include acarbonate base. In some cases, the carbonate base can be sodiumcarbonate, potassium carbonate, cesium carbonate, sodium bicarbonate,potassium bicarbonate, cesium bicarbonate, or a combination thereof. Theamount of carbonate base in the reaction product mixture can depend onthe amount of carbonate base added at the beginning of the reaction andthe amount that is consumed during the reaction. In some cases, one moleof a carbonate base can react with one mole of the aminophenol duringthe reaction to form the polymeric amine synergist. Thus, one mole ofthe carbonate base is equal to 1 equivalent for a single mole ofaminophenol. In some examples, the amount of carbonate base used in thereaction can be 1 equivalent or more of the carbonate base, relative tothe amount of the aminophenol present in the reaction. In furtherexamples, the amount of carbonate base can be from about 1 equivalent toabout 2 equivalents, relative to the amount of the aminophenol. In aspecific example, the amount of carbonate base can be from about 1equivalent to about 1.2 equivalents or from about 1.1 equivalents toabout 1.2 equivalents, relative to the amount of the aminophenol. Inexamples where all the aminophenol reacts to form the polymeric aminesynergist, the amount of carbonate base left in the reaction productmixture can be, for example, up to about 1 equivalent, from about 0.1equivalent to about 1 equivalent, up to about 0.2 equivalent, or fromabout 0.1 equivalent to about 0.2 equivalent, with respect to the amountof aminophenol used in the reaction.

The present disclosure also extends to photo curable inks. In someexamples, a UV curable ink or an LED curable ink can be used, e.g., UVand/or LED curable ink. These inks can include a photo reactive binder,e.g., UV and/or LED, a photo initiator, a polymeric amine synergist, acolorant, and a liquid vehicle including a co-solvent and water. Thepolymeric amine synergist can be an aminobenzene modified with apolyether chain connecting to the aminobenzene through an ether linkage.

In some cases, the photo reactive binder can include a UV curablepolyurethane and hydrophobic radiation-curable monomers. In one example,the photo reactive binder can include a water dispersible(meth)acrylated polyurethane, such as NeoRad® R-441 by NeoResins(Avecia). Other examples of photo (UV) reactive binders can includeUcecoat® 7710, Ucecoat® 7655 (available from Cytec), Neorad® R-440,Neorad® R-441, Neorad® R-447, Neorad® R-448 (available from DSMNeoResins), Bayhydrol® UV 2317, Bayhydrol® UV VP LS 2348 (available fromBayer), Lux 430, Lux 399, Lux 484 (available from Alberdingk Boley),Laromer® LR 8949, Laromer® LR 8983, Laromer® PE 22WN, Laromer® PE 55WN,Laromer® UA 9060 (available from BASF), or combinations thereof.

In general, ultraviolet (UV) curable ink can be cured after printing byapplication of UV radiation or light. Typically, UV curable inks includemonomers that form polymers by free radical polymerization. The growingend of each polymer chain is a radical that reacts with additionalmonomers, transferring the radical to the end of the chain as eachmonomer is added. A photo initiator is used to form the first radicalsto begin the polymerization process. The photo initiator is capable ofabsorbing UV light to generate radicals to react with the monomers. Twotypes of photo initiators can be used in UV curable compositions. Type Iphoto initiators are unimolecular photo initiators that undergo ahemolytic bond cleavage upon absorption of UV light, forming radicals.Type II photo initiators are bimolecular photo initiators. These areused as a system of a photo initiator with a synergist, which cantogether form radicals upon exposure to UV light. Some type II photoinitiators react by hydrogen abstraction from the synergist to the photoinitiator.

The polymeric amine synergists of the present disclosure can be usedwith type II photo initiators. The photo curable ink can include a typeII photo initiator so that the photo initiator and amine synergisttogether can generate radicals during photo curing, e.g., UV curing orLED curing or UV LED curing. The type II photo initiators can act as theprimary photo initiator in the photo curable ink, or they can act as asensitizer for another co-photo initiator. Therefore, the photo curableink can in some cases include a second photo initiator. Examples ofradical co-photo initiators include, by way of illustration and notlimitation, 1-hydroxy-cyclohexylphenylketone, benzophenone,2,4,6-trimethylbenzo-phenone, 4-methylbenzophenone, diphenyl-(2,4,6-trimethylbenzoyl)phosphine oxide, phenyl bis(2,4,6trimethylbenzoyl)phosphine oxide,2-hydroxy-2-methyl-1-phenyl-1-propanone, benzyl-dimethyl ketal,2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one, orcombinations thereof. Non-limiting examples of additional photoinitiators include alpha amino ketone UV photo initiators such as Ciba®Irgacure® 907, Ciba® Irgacure® 369, and Ciba® Irgacure® 379; bisacylphosphine oxide (BAPO) UV photo initiators such as Irgacure® 819,Darocur® 4265, and Darocur® TPO; alpha hydroxy ketone UV photoinitiators such as Irgacure® 184 and Darocur® 1173; including photoinitiators with or without sensitizers such as Darocur® ITX (2-isopropylthioxanthone).

The colorant in the photo curable ink can be a pigment, a dye, or acombination thereof. In some examples, the colorant can be present in anamount from 0.5 wt % to 10 wt % in the photo curable ink. In oneexample, the colorant can be present in an amount from 1 wt % to 5 wt %.In another example, the colorant can be present in an amount from 5 wt %to 10 wt %.

In some examples, the colorant can be a dye. The dye can be nonionic,cationic, anionic, or a mixture of nonionic, cationic, and/or anionicdyes. Specific examples of dyes that can be used include, but are notlimited to, Sulforhodamine B, Acid Blue 113, Acid Blue 29, Acid Red 4,Rose Bengal, Acid Yellow 17, Acid Yellow 29, Acid Yellow 42, AcridineYellow G, Acid Yellow 23, Acid Blue 9, Nitro Blue Tetrazolium ChlorideMonohydrate or Nitro BT, Rhodamine 6G, Rhodamine 123, Rhodamine B,Rhodamine B Isocyanate, Safranine O, Azure B, and Azure B Eosinate,which are available from Sigma-Aldrich Chemical Company (St. Louis,Mo.). Examples of anionic, water-soluble dyes include, but are notlimited to, Direct Yellow 132, Direct Blue 199, Magenta 377 (availablefrom Ilford AG, Switzerland), alone or together with Acid Red 52.Examples of water-insoluble dyes include azo, xanthene, methine,polymethine, and anthraquinone dyes. Specific examples ofwater-insoluble dyes include Orasol® Blue GN, Orasol® Pink, and Orasol®Yellow dyes available from Ciba-Geigy Corp. Black dyes may include, butare not limited to, Direct Black 154, Direct Black 168, Fast Black 2,Direct Black 171, Direct Black 19, Acid Black 1, Acid Black 191, MobayBlack SP, and Acid Black 2.

In other examples, the colorant can be a pigment. The pigment can beself-dispersed with a polymer, oligomer, or small molecule; or can bedispersed with a separate dispersant. Suitable pigments include, but arenot limited to, the following pigments available from BASF: Paliogen®Orange, Heliogen® Blue L 6901F, Heliogen® Blue NBD 7010, Heliogen® BlueK 7090, Heliogen® Blue L 7101F, Paliogen® Blue L 6470, Heliogen® Green K8683, and Heliogen® Green L 9140. The following black pigments areavailable from Cabot: Monarch® 1400, Monarch® 1300, Monarch® 1100,Monarch® 1000, Monarch® 900, Monarch® 880, Monarch® 800, and Monarch®700. The following pigments are available from CIBA: Chromophtal® Yellow3G, Chromophtal® Yellow GR, Chromophtal® Yellow 8G, Igrazin® Yellow 5GT,Igrantee Rubine 4BL, Monastral® Magenta, Monastral® Scarlet, Monastral®Violet R, Monastral® Red B, and Monastral® Violet Maroon B. Thefollowing pigments are available from Degussa: Printex® U, Printex® V,Printex® 140U, Printex® 140V, Color Black FW 200, Color Black FW 2,Color Black FW 2V, Color Black FW 1, Color Black FW 18, Color Black S160, Color Black S 170, Special Black 6, Special Black 5, Special Black4A, and Special Black 4. The following pigment is available from DuPont:Tipure® R-101. The following pigments are available from Heubach:Dalamar® Yellow YT-858-D and Heucophthal Blue G XBT-583D. The followingpigments are available from Clariant: Permanent Yellow GR, PermanentYellow G, Permanent Yellow DHG, Permanent Yellow NCG-71, PermanentYellow GG, Hansa Yellow RA, Hansa Brilliant Yellow 5GX-02, HansaYellow-X, Novoperm® Yellow HR, Novoperm® Yellow FGL, Hansa BrilliantYellow 10GX, Permanent Yellow G3R-01, Hostaperm® Yellow H4G, Hostaperm®Yellow H3G, Hostaperm® Orange GR, Hostaperm® Scarlet GO, and PermanentRubine F6B. The following pigments are available from Mobay: Quindo®Magenta, Indofast® Brilliant Scarlet, Quindo® Red R6700, Quindo® RedR6713, and Indofast® Violet. The following pigments are available fromSun Chemical: L74-1357 Yellow, L75-1331 Yellow, and L75-2577 Yellow. Thefollowing pigments are available from Columbian: Raven® 7000, Raven®5750, Raven® 5250, Raven® 5000, and Raven® 3500. The following pigmentis available from Sun Chemical: LHD9303 Black. Any other pigment and/ordye can be used that is useful in modifying the color of the UV curableink. Additionally, the colorant can include a white pigment such astitanium dioxide, or other inorganic pigments such as zinc oxide andiron oxide.

The components of the photo curable ink can be selected to give the inkgood ink jetting performance. Besides the curable binder, polymericamine synergists, photo initiator, and the colorant, the photo curableink can also include a liquid vehicle. Liquid vehicle formulations thatcan be used in the photo curable ink can include water and one or moreco-solvents present in total at from 1 wt % to 50 wt %, depending on thejetting architecture. Further, one or more non-ionic, cationic, and/oranionic surfactant can be present, ranging from 0.01 wt % to 20 wt % (ifpresent). In one example, the surfactant can be present in an amountfrom 5 wt % to 20 wt %. The liquid vehicle can also include dispersantsin an amount from 5 wt % to 20 wt %. The balance of the formulation canbe purified water, or other vehicle components such as biocides,viscosity modifiers, materials for pH adjustment, sequestering agents,preservatives, and the like. In one example, the liquid vehicle can bemore than 50 wt % water.

Classes of co-solvents that can be used can include organic co-solventsincluding aliphatic alcohols, aromatic alcohols, diols, glycol ethers,polyglycol ethers, caprolactams, formamides, acetamides, and long chainalcohols. Examples of such compounds include primary aliphatic alcohols,secondary aliphatic alcohols, 1,2-alcohols, 1,3-alcohols, 1,5-alcohols,ethylene glycol alkyl ethers, propylene glycol alkyl ethers, higherhomologs (C₆-C₁₂) of polyethylene glycol alkyl ethers, N-alkylcaprolactams, unsubstituted caprolactams, both substituted andunsubstituted formamides, both substituted and unsubstituted acetamides,and the like. Specific examples of solvents that can be used include,but are not limited to, 2-pyrrolidinone, N-methylpyrrolidone,2-hydroxyethyl-2-pyrrolidone, 2-methyl-1,3-propanediol, tetraethyleneglycol, 1,6-hexanediol, 1,5-hexanediol and 1,5-pentanediol.

One or more surfactants can also be used, such as alkyl polyethyleneoxides, alkyl phenyl polyethylene oxides, polyethylene oxide blockcopolymers, acetylenic polyethylene oxides, polyethylene oxide(di)esters, polyethylene oxide amines, protonated polyethylene oxideamines, protonated polyethylene oxide amides, dimethicone copolyols,substituted amine oxides, and the like. The amount of surfactant addedto the formulation of this disclosure may range from 0.01 wt % to 20 wt%. Suitable surfactants can include, but are not limited to, liponicesters such as Tergitol™ 15-S-12, Tergitol™ 15-S-7 available from DowChemical Company, LEG-1 and LEG-7; Triton™ X-100, Triton™ X-405available from Dow Chemical Company; LEG-1, and sodium dodecylsulfate.

Consistent with the formulation of this disclosure, various otheradditives can be employed to optimize the properties of the inkcomposition for specific applications. Examples of these additives arethose added to inhibit the growth of harmful microorganisms. Theseadditives may be biocides, fungicides, and other microbial agents, whichare routinely used in ink formulations. Examples of suitable microbialagents include, but are not limited to, NUOSEPT® (Nudex, Inc.),UCARCIDE™ (Union carbide Corp.), VANCIDE® (R.T. Vanderbilt Co.), PROXEL®(ICI America), and combinations thereof.

Sequestering agents, such as EDTA (ethylene diamine tetra acetic acid),may be included to eliminate the deleterious effects of heavy metalimpurities, and buffer solutions may be used to control the pH of theink. From 0.01 wt % to 2 wt %, for example, can be used if present.Viscosity modifiers and buffers may also be present, as well as otheradditives to modify properties of the ink as desired. Such additives canbe present at from 0.01 wt % to 20 wt % if present.

Table 1 shows the composition of an example of a photo curable ink,e.g., UV LED curable ink, formulation example in accordance with thepresent disclosure. The ink can be formulated by mixing theseingredients or by other formulations. The pH of the ink can then beadjusted. In one example, the ingredients can be stirred for 30 minutes,and then aqueous potassium hydroxide can be added to adjust the pH to 7to 12, or in one example, about 8.5. It is noted that though waterconcentrations are listed as “balance,” it is understood that thebalance of components can include other liquid vehicle components orminor amounts of solids often present in inkjet ink compositions.

TABLE 1 Component Weight Percent Photo reactive binder  1-20% (UVreactive polymer) Sensitizer *0-10% Co-photo initiator *0-10% Polymericamine synergist 0.15-10%  Surfactant  0-20% Anti-kogation agent  0-5%Colorant 0.5-10%  Organic Co-solvent 0.1-50%  Water Balance *As noted,when a sensitizer is included, the amounts of sensitizer and co-photoinitiator can be greater than 0%.

The photo curable ink can be used to print on a broad selection ofsubstrates including untreated plastics, flexible as well as rigid,porous substrates such as paper, cardboard, foam board, textile, andothers. The ink has a good adhesion on a variety of substrates. Thephoto curable ink also has a good viscosity, enabling good printingperformances and enables the ability to formulate inks suitable forinkjet application. In some examples, the ink can be formulated forthermal inkjet printing. The photo curable ink composition of thepresent disclosure enables high printing speed and is very well suitedfor a use in digital inkjet printing.

The polymeric amine synergists of the present disclosure can be stablein aqueous environments at pH from 7 to 12 or higher. Thus, the photocurable ink can be formulated to have a pH from 7 to 12. In someexamples, the photo curable ink can have a pH of 8 to 12. In onespecific example, the photo curable ink can have a pH of about 8.5.

The polymeric amine synergists can exhibit less migration in cured inkcompared with small molecule synergists. The photo curable binder in theink can include polymers or monomers that polymerize or cross-linkduring the curing process. As the binder cures, the polymeric aminesynergist can become locked into the cured binder due to the longpolyether chain of the polymeric amine synergist. Therefore, the photocurable ink can be formulated so that there is little or no migration ofthe polymeric amine synergist in the ink after curing.

The present disclosure also extends to a method of making a photocurable ink. The method includes mixing a photo reactive binder; a photoinitiator; optionally a co-photo initiator; a polymeric amine synergist;a colorant; and a liquid vehicle including co-solvent and water. Thepolymeric amine synergist can be an aminobenzene modified with apolyether chain connecting to the aminobenzene through an ether linkage.The photo curable ink can be UV curable, and in one specific example, UVLED curable. In one example, the method can also include adjusting thepH of the ink to be from 7 to 12. In another example, the method caninclude adjusting the pH of the ink to be 8 or higher.

It is to be understood that this disclosure is not limited to theparticular process steps and materials disclosed herein because suchprocess steps and materials may vary somewhat. It is also to beunderstood that the terminology used herein is used for the purpose ofdescribing particular examples only. The terms are not intended to belimiting because the scope of the present disclosure is intended to belimited only by the appended claims and equivalents thereof.

It is noted that, as used in this specification and the appended claims,the singular forms “a,” “an,” and “the” include plural referents unlessthe context clearly dictates otherwise.

As used herein, “photoactive agent” refers to materials that participatein the initiation of photo polymerization, particularly materials thatact as a photo initiator or a sensitizer for a photo initiator.

As used herein, “synergist” refers to a material that can be used with atype-II photo initiator to initiate polymerization of a curable binder.

As used herein, “UV curable” refers to compositions that can be cured byexposure to ultraviolet light from any UV source such as a mercury vaporlamp, UV LED source, or the like. Mercury vapor lamps emit highintensity light at wavelengths from 240 nm to 270 nm and 350 nm to 380nm. “LED curable” refers to compositions that can be cured either byultraviolet light from an ultraviolet LED. Ultraviolet LEDs emit lightat specific wavelengths. For example, ultraviolet LEDs are available at365 nm and 395 nm wavelengths, among others. The term “photo curable”refers generally to compositions that can be cured by exposure to lightfrom any wavelength suitable for the composition being cured. Typically,the photo curable composition will be UV curable, and in some cases UVLED curable.

As used herein, “liquid vehicle” or “ink vehicle” refers to a liquidfluid in which colorant is placed to form an ink. A wide variety of inkvehicles may be used with the systems and methods of the presentdisclosure. Such ink vehicles may include a mixture of a variety ofdifferent agents, including, surfactants, solvents, co-solvents,anti-kogation agents, buffers, biocides, sequestering agents, viscositymodifiers, surface-active agents, water, etc.

As used herein, “colorant” can include dyes and/or pigments.

As used herein, “dye” refers to compounds or molecules that absorbelectromagnetic radiation or certain wavelengths thereof. Dyes canimpart a visible color to an ink if the dyes absorb wavelengths in thevisible spectrum.

As used herein, “pigment” generally includes pigment colorants, magneticparticles, aluminas, silicas, and/or other ceramics, organo-metallics orother opaque particles, whether or not such particulates impart color.Thus, though the present description primarily exemplifies the use ofpigment colorants, the term “pigment” can be used more generally todescribe not only pigment colorants, but other pigments such asorganometallics, ferrites, ceramics, etc. In one specific example,however, the pigment is a pigment colorant.

As used herein, “ink-jetting” or “jetting” refers to compositions thatare ejected from jetting architecture, such as ink-jet architecture.Ink-jet architecture can include thermal or piezo architecture.Additionally, such architecture can print varying drop sizes such asless than 10 picoliters, less than 20 picoliters, less than 30picoliters, less than 40 picoliters, less than 50 picoliters, etc.

The term “residual” when referring to remaining components aftercarrying out methods of the present disclosure can be up to 5 wt %, upto 3 wt %, up to 1 wt %, or up to 0.1 wt %, for example. To be clear,residual amounts of components are not necessarily present whenreactants are fully consumed in a chemical reaction and such examplesare included in the context of the present disclosure, but inpracticality in many instances, some residual components can remain.

As used herein, the term “substantial” or “substantially” when used inreference to a quantity or amount of a material, or a specificcharacteristic thereof, refers to an amount that is sufficient toprovide an effect that the material or characteristic was intended toprovide. The exact degree of deviation allowable may in some casesdepend on the specific context.

As used herein, the term “about” is used to provide flexibility to anumerical range endpoint by providing that a given value may be “alittle above” or “a little below” the endpoint. The degree offlexibility of this term can be dictated by the particular variable anddetermined based on the associated description herein.

As used herein, a plurality of items, structural elements, compositionalelements, and/or materials may be presented in a common list forconvenience. However, these lists should be construed as though eachmember of the list is individually identified as a separate and uniquemember. Thus, no individual member of such list should be construed as ade facto equivalent of any other member of the same list solely based ontheir presentation in a common group without indications to thecontrary.

Concentrations, amounts, and other numerical data may be expressed orpresented herein in a range format. It is to be understood that such arange format is used merely for convenience and brevity and thus shouldbe interpreted flexibly to include not only the numerical valuesexplicitly recited as the limits of the range, but also to includeindividual numerical values or sub-ranges encompassed within that rangeas if each numerical value and sub-range is explicitly recited. As anillustration, a numerical range of “about 1 wt % to about 5 wt %” shouldbe interpreted to include not only the explicitly recited values ofabout 1 wt % to about 5 wt %, but also include individual values andsub-ranges within the indicated range. Thus, included in this numericalrange are individual values such as 2, 3.5, and 4 and sub-ranges such asfrom 1-3, from 2-4, and from 3-5, etc. This same principle applies toranges reciting only one numerical value. Furthermore, such aninterpretation should apply regardless of the breadth of the range orthe characteristics being described.

EXAMPLES

The following illustrates several examples of the present disclosure.However, it is to be understood that the following are only illustrativeof the application of the principles of the present disclosure. Numerousmodifications and alternative compositions, methods, and systems may bedevised without departing from the spirit and scope of the presentdisclosure. The appended claims are intended to cover such modificationsand arrangements.

Example 1

Synthesis of 4-dimethylaminophenol: To a solution of 4-aminophenol(54.65 g, 0.5 mol) in 600 mL of methanol was added formaldehyde (90 g,3.0 mol) at room temperature. The above solution was cooled to −5° C.using a salted ice bath, and then sodium borohydride (113.5 g, 3.0 mol)was added portion wise. This reaction generated a significant amount ofhydrogen gas, and therefore the sodium borohydride was added slowly forsafety. After adding the sodium borohydride, the mixture was stirred atroom temperature for 24 hours. The reaction was quenched via addition ofice-water and then extracted with chloroform (3×100 mL). The organiclayer was combined and dried over sodium sulfate. Sodium sulfate wasremoved by filtration and the solvent was evaporated in vacuum. Theresidue was further purified by flash chromatography, giving the desired4-dimethylaminophenol (56.3 g, 82% yield).

Example 2

Synthesis of dichloro-polyethylene glycol-600: A mixture of polyethyleneglycol-600 (100 grams, 0.1 mol), thionyl chloride (60 grams, 0.5 mol)and 0.1 grams of N-dimethylformamide (DMF) was heated to reflux for 5hours. After cooling down to room temperature, 20 mL of methanol wasadded slowly to the solution and stirred for 1 hour. Then the methanoland unreacted thionyl chloride were removed by vacuum to give thedesired dichloro-polyethylene glycol (102 grams, 96% yield).

Example 3

Synthesis of polyethylene glycol di-tosylate: To a solution ofpolyethylene glycol-600 (100 grams, 0.167 mol) in 250 mL ofdichloromethane was added pyridine (14 mL, 0.16 mol). The above solutionwas cooled to 0° C. and then p-toluenesulfonyl chloride (22.88 grams,0.12 mol) was added portion-wise at 0° C. under N₂. The resultingsolution was poured into ice-water. The organic layer was separated, andthe aqueous layer was extracted with chloroform (2×50 mL). The combinedorganic layer was washed with water and dried over sodium sulfate. Thesodium sulfate was filtered off and evaporation of solvent gave thedesired polyethylene glycol di-tosylate (128 grams, 85% yield).

Example 4

Synthesis of chloro mono-methyl polyethylene glycol ether: A mixture ofmono-methyl polyethylene glycol ether 550 (100 grams, 0.18 mol), thionylchloride (60 grams, 0.5 mol) and 0.1 grams of N-dimethylformamide (DMF)was heated to reflux for 5 hours. After cooling down to roomtemperature, 20 mL of methanol was added slowly to the solution andstirred for 1 hour. Then the methanol and unreacted thionyl chloridewere removed by vacuum to give the desired chloro mono-methylpolyethylene glycol ether (100 grams, 97% yield).

Example 5

Synthesis of mono-methyl polyethylene glycol ether tosylate: To asolution of mono-methyl polyethylene glycol ether 550 (100 grams, 0.182mol) in 250 mL of dichloromethane was added pyridine (28 mL, 0.32 mol).The above solution was cooled to 0° C. and then p-toluenesulfonylchloride (34.89 grams, 0.183 mol) was added portion-wise at 0° C. underN₂. The resulting solution was poured into ice-water. The organic layerwas separated, and the aqueous layer was extracted with chloroform (2×50mL). The combined organic layer was washed with water and dried oversodium sulfate. The sodium sulfate was filtered off and evaporation ofsolvent gave the desired mono-methyl polyethylene glycol tosylate (115grams, 90% yield).

Example 6

Synthesis of bis(4-dimethylaminophenol) derivative of PEG 600 fromdichloride: A mixture of 4-dimethylaminophenol (6.86 g, 50 mmol) anddichloro-polyethylene glycol-600 (15.88 g, 25 mmol) in 50 mL of DMF inthe presence of sodium carbonate (5.3 g, 50 mmol) was heated to refluxfor 3 hours. After cooling down to room temperature, the inorganic saltswere removed by filtration. Evaporation of solvent by rotary evaporatorgave a residue, which was further purified by flash chromatography,giving rise to the desired bis(4-dimethylaminophenol) derivative of PEG600 (39.8 g, 95% yield).

Example 7

Synthesis of bis-(4-dimethylaminophenol) derivative of PEG 600 fromdi-tosylate: A mixture of 4-dimethylaminophenol (6.86 g, 50 mmol) andpolyethylene glycol-600 di-tosylate (22.70 g, 25 mmol) in 50 mL of DMFin the presence of sodium carbonate (5.3 g, 50 mmol) was heated toreflux for 2 hours. Then DMF was removed by distillation. After coolingdown to room temperature, the solid was filtered off by simplefiltration. Evaporation of solvent by rotary evaporator gave a residue,which was further purified by flash chromatography, giving rise to thedesired bis(4-dimethylaminophenol) derivative of PEG 600 (35.62 g, 85%yield).

Example 8

Synthesis of mono-(4-dimethylaminophenol) derivative of PEG 550 fromchloride: A mixture of 4-dimethylaminophenol (6.86 g, 50 mmol) andchloro mono-methyl polyethylene glycol ether (28.38 g, 50 mmol) in 50 mLof DMF in the presence of sodium carbonate (5.3 g, 50 mmol) was heatedto reflux for 2 hours. Then DMF was removed by distillation. Aftercooling down to room temperature, the solid was filtered off by simplefiltration. Evaporation of solvent by rotary evaporator gave a residue,which was further purified by flash chromatography, giving rise to thedesired mono-(4-dimethylaminophenol) derivative of PEG 550 (28.43 g, 85%yield).

Example 9

Synthesis of mono-(4-dimethylaminophenol) derivative of PEG 550 fromtosylate: A mixture of 4-dimethylaminophenol (6.86 g, 50 mmol) andmono-methyl polyethylene glycol ether 550 tosylate (35.20 g, 50 mmol) in50 mL of DMF in the presence of sodium carbonate (5.3 g, 50 mmol) washeated to reflux for 2 hours. Then DMF was removed by distillation.After cooling down to room temperature, the solid was filtered off bysimple filtration. Evaporation of solvent by rotary evaporator gave aresidue, which was further purified by flash chromatography, giving riseto the desired mono-(4-dimethylaminophenol) derivative of PEG 550 (30.1g, 90% yield).

Example 10

Inkjet inks are prepared in accordance with the Table 1 above, eachusing one of polymeric amine synergists prepared in Examples 6-9.Specifically, inks are prepared that include the polymeric aminesynergist; a photo reactive binder; a photo initiator; a colorant; and aliquid vehicle including co-solvent and water.

While the present technology has been described with reference tocertain examples, those skilled in the art will appreciate that variousmodifications, changes, omissions, and substitutions can be made withoutdeparting from the spirit of the disclosure. It is intended, therefore,that the disclosure be limited only by the scope of the followingclaims.

What is claimed is:
 1. A polymeric amine synergist composition,comprising a polymeric amine synergist including an aminobenzenemodified with a polyether chain connecting to the aminobenzene throughan ether linkage, wherein the polymeric amine synergist is present in areaction product mixture with either i) an aminophenol, or ii) acarbonate base.
 2. The polymeric amine synergist composition of claim 1,wherein the reaction product mixture comprises a carbonate base that issodium carbonate, potassium carbonate, cesium carbonate, sodiumbicarbonate, potassium bicarbonate, cesium bicarbonate, or a combinationthereof.
 3. The polymeric amine synergist composition of claim 2,wherein the carbonate base is present in an amount up to about 1.0equivalent with respect to a total amount of aminophenol used to formthe polymeric amine synergist.
 4. A method of making a polymeric aminesynergist, comprising reacting an aminophenol, a polyether modified witha leaving group, and a carbonate base in a single reaction step to yielda polymeric amine synergist that is an aminobenzene modified with apolyether chain connecting to the aminobenzene through an ether linkage.5. The method of claim 4, wherein the carbonate base is sodiumcarbonate, potassium carbonate, cesium carbonate, sodium bicarbonate,potassium bicarbonate, cesium bicarbonate, or a combination thereof. 6.The method of claim 4, wherein the carbonate base is reacted in anamount from about 1.0 to about 2.0 equivalents with respect to a totalamount of the aminophenol.
 7. The method of claim 4, wherein the leavinggroup is chloride, bromide, iodide, tosylate, triflate, or a combinationthereof.
 8. The method of claim 4, wherein the aminophenol has thegeneral formula:

wherein R₁ and R₂ are independently a hydrogen atom, an unsubstitutedalkyl, a substituted alkyl, an unsubstituted alkenyl, a substitutedalkenyl, an unsubstituted aryl, a substituted aryl, an unsubstitutedaralkyl, a substituted aralkyl, a halogen atom, —NO₂, —O—R_(d),—CO—R_(d), —CO—O—R_(d), —O—CO—R_(d), —CO—NR_(d)R_(e), —NR_(d)R_(e),—NR_(d)—CO—R_(e), —NR_(d)—CO—O—R_(e), —NR_(d)—CO—NR_(e)R_(f), —SR_(d),—SO—R_(d), —SO₂—R_(d), —SO₂—O—R_(d), —SO₂NR_(d)R_(e), or aperfluoroalkyl group, wherein R_(d), R_(e), and R_(f) are independentlya hydrogen atom, an unsubstituted alkyl, a substituted alkyl, anunsubstituted alkenyl, a substituted alkenyl, an unsubstituted aryl, asubstituted aryl, an unsubstituted aralkyl, or a substituted aralkyl. 9.The method of claim 4, wherein the polyether modified with the leavinggroup is formed by reacting a leaving group with a polyether chain,wherein the polyether chain comprises polyethylene glycol, polypropyleneglycol, or a copolymer of polyethylene glycol and polypropylene glycol.10. The method of claim 9, wherein the polyether chain is PEG 550, PEG600, or PEG
 1000. 11. The method of claim 4, wherein the polyethermodified with the leaving group has a general formula of:

wherein R₃ is a hydrogen atom, an unsubstituted alkyl, a substitutedalkyl, an unsubstituted alkenyl, a substituted alkenyl, an unsubstitutedaryl, a substituted aryl, an unsubstituted aralkyl, a substitutedaralkyl, a halogen atom, —NO₂, —O—R_(d), —CO—R_(d), —CO—O—R_(d),—O—CO—R_(d), —CO—NR_(d)R_(e), —NR_(d)R_(e), —NR_(d)—CO—R_(e),—NR_(d)—CO—O—R_(e), —NR_(d)—CO—NR_(e)R_(f), —SR_(d), —SO—R_(d),—SO₂—R_(d), —SO₂—O—R_(d), —SO₂NR_(d)R_(e), or a perfluoroalkyl group,wherein R_(d), R_(e), and R_(f) are independently a hydrogen atom, anunsubstituted alkyl, a substituted alkyl, an unsubstituted alkenyl, asubstituted alkenyl, an unsubstituted aryl, a substituted aryl, anunsubstituted aralkyl, or a substituted aralkyl, wherein Y is chloride,bromide, iodide, tosylate, or triflate, and wherein n is an integer from5 to
 200. 12. The method of claim 4, wherein the polymeric aminesynergist has the formula:

wherein n is an integer from 10 to
 25. 13. The method of claim 4,wherein the polymeric amine synergist has a weight average molecularweight from about 500 Mw to about 5000 Mw, a water solubility of atleast 0.5 wt %, is stable in water at a pH from 7 to 12, or combinationsthereof.
 14. A method of making a photo curable ink, comprising:preparing a polymeric amine synergist in accordance with claim 4; andadmixing: the polymeric amine synergist, a photo reactive binder, aphoto initiator, a colorant, and a liquid vehicle including co-solventand water.
 15. A photo curable ink, comprising: a polymeric aminesynergist composition, comprising a polymeric amine synergist includingan aminobenzene modified with a polyether chain connecting to theaminobenzene through an ether linkage; an aminophenol, or a carbonatebase, or combination thereof; a photo reactive binder; a photoinitiator; a colorant; and a liquid vehicle including co-solvent andwater.